The field of the invention pertains to punches and dies for forming holes and depressions in metals. In particular, the invention pertains to devices and accessories for preventing work pieces from adhering to punches during high-speed high production manufacturing.
Examples of modern punch retainers are shown in applicant's previous U.S. Pat. Nos. 5,357,835, 5,410,932 and Des. 351,395. Views of these punch retainers are also shown in FIGS. 1, 2, 8 and 9. Modern punches for certain applications utilize a polyurethane cup that fits over the punch and is attached to the punch retainer by a two-piece metal stripper retainer. The two-piece stripper retainer was developed to provide adequate axial support for the cup. Although inexpensively stamped from sheet steel, the two-piece stripper retainer does not rigidly and accurately retain the polyurethane cup to the punch retainer to the degree desired. In addition, the two-piece stripper retainer will not fit the industries' new smaller footprint ball-lock punch retainer for round shaped punches.